If there is a proxy required to contact the Managed Server machine from the Admin Server machine through https, you need to provide the Proxy Server Setting.
During installation of Managed Server, in the screen where you have to enter the Host Name, Webserver Port, SSL Port of the Admin Server, click on the Proxy Server check box to enter the Host Name, Webserver port, username and password of the proxy server.
In case, if you give wrong proxy configuration information during Installation, you can change the info by editing the <AppManager Home/conf/AMServer.properties.